The present invention relates to novel tetrazolinone derivatives, to processes for their preparation and to their use as herbicides.
It has already been known that certain kinds of tetrazole derivatives show herbicidal activity (Japanese Laid-open Patent Application Nos. 12275/1999 and 21280/1999). Moreover, it has further already been known, that certain kinds of heterocyclic derivatives also show herbicidal activity (U.S. Pat. Nos. 5,834,402 and 5,846,906).
There have now been found novel tetrazolinone derivatives of the general formula (I) 
wherein
R1 represents halogen, C1-4 alkyl, C1-4 haloalkyl, C1-4 alkoxy, C1-4 alkylthio, C1-4 alkylsulfonyl, C1-4 alkylsulfonyloxy, C2-5 alkoxycarbonyl, C2-6 alkoxyalkyl, C2-6 alkylthioalkyl, nitro or cyano,
R2 represents a hydrogen atom, C1-6 alkyl, C3-6 cycloalkyl which may be optionally substituted with halogen or C1-3 alkyl, C1-4 haloalkyl, or phenyl which may be optionally substituted with halogen, C1-3 alkyl, C1-3 haloalkyl or nitro,
m represents 0, 1 or 2; while the two R1 substituents may be identical or different, in case m represents 2,
n represents 0 or 1, and
Q represents one of the following groups 
in which
R3, R4, R5, R6, R7, and R8 each independently represent a hydrogen atom or C1-4 alkyl.
or
R3 and R8 may form an ethylene chain together,
R9 represents C1-4 alkyl,
R10 represents C1-4 alkyl or C3-6 cycloalkyl which may be optionally substituted with methyl.
The compounds of the general formula (I), according to the invention, can be obtained by a process in which
a) compounds of the general formula (IIa) 
wherein
R1, R2, m and n have the same definition as aforementioned, and
T1 represents one of the following groups 
in which
R3, R4, R5, R6, R7, R8 and R9 have the same definition as mentioned above,
are reacted to a rearrangement in the presence of a base and a cyanide,
or
b) in case that Q represents group (Q-2):
compounds of the general formula (IIb) 
wherein
R1, R2, m and n have the same definitions as mentioned above, and
T2 represents one of the following groups; 
in which
R9 has the same definition as mentioned above,
are reacted to a rearrangement in the presence of a base,
or
c) in case that Q represents group (Q-3):
compounds of the general formula (III) 
wherein
R1, R2, R10, m and n have the same definitions as mentioned above, and
R11, represents C1-4 alkyl, preferably methyl or ethyl,
are reacted with hydroxylamine,
or
d) in case that Q represents group (Q-4):
compounds of the general formula (Ib) 
wherein
R1, R2, R10, m and n have the same definition as mentioned above,
are reacted to a ring-opening in the presence of a base.